Conventionally, there is a weighing and packaging system which charges objects to be packaged having a fixed volume into package bags conveyed successively in a line shape to manufacture package products (e.g., see patent document 1). FIG. 8 shows an example of such a conventional weighing and packaging system. FIG. 8(a) is a side view of the conventional weighing and packaging system. FIG. 8(b) is a plan view showing major components of the weighing and packaging system.
The weighing and packaging system includes a packaging machine 20 and a powder material supplying device 50 for supplying a powder material as objects to be packaged. In the packaging machine 20, an elongate film P is wound back from a film roll (not shown), horizontally conveyed successively via several rollers, and bent in a watershoot shape to have a fold line at a lower side through a film guide 21. The lower end portions of feeding funnels 23 are sequentially inserted into a space of the two-fold film P1. Then, sealing bars 22 (fixing/heating bars 22a, tilting levers 22b) sequentially sandwich the two-fold film from both sides such that heating surfaces of the fixing/heating bars 22a thermally seal the film with a small width in a width direction of the film, thereby forming side seal portions P2 at constant intervals. A number of package bags P3 defined by the side seal portions P2 are formed successively in the longitudinal direction of the film. The package bags P3 are conveyed successively with the lower end portions of the feeding funnels 23 inserted into openings formed at the upper edges of the package bags P3.
The powder material is supplied from the powder material supplying device 50 located above with a constant amount through the openings of measuring cups 54 and is charged into the respective package bags P3 via the feeding funnels 23. The powder material supplying device 50 includes a hopper 51 storing the powder material, a rotary container 52 which receives the powder material through the lower end opening of the hopper 51 and has a flat bottom plate 53, plural tubular measuring cups 54 having a constant volume and penetrating downward through the periphery of the bottom plate 53, a measuring board (not shown) which is fixed on the bottom plate 53 and positioned in close proximity to the upper end opening surfaces of the measuring cups 54 to charge the powder material into the measuring cups 54 precisely up to the upper edges thereof, and shutters 55 for opening and closing the lower end opening surfaces of the measuring cups 54.
The film charged with the powder material in the package bags P3 by the powder material supplying device 50 is conveyed successively and passes through a turn-back roller 24. An upper edge sealing device 25 thermally seals the upper edge portions of the package bags P3 successively to form upper edge seal portions P4, thereby sealing the package bags. The film is further conveyed, and a cutting device 26 perforates the side seal portions P2 to form seams, or cuts them, so that the package bags P3 are sequentially cut and separated away from each other. Thus, the package products are manufactured.    Patent document 1: Japanese Laid-Open Patent Application Publication No. 2004-99136